scholarly journals Numerical Study and Field Monitoring of the Ground Deformation Induced by Large Slurry Shield Tunnelling in Sandy Cobble Ground

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Chengping Zhang ◽  
Yi Cai ◽  
Wenjun Zhu
Keyword(s):  
Urban Areas ◽  
Numerical Study ◽  
Ground Deformation ◽  
Three Dimensional ◽  
Field Measurements ◽  
Horizontal Displacement ◽  
Railway Station ◽  
Excavation Process ◽  
Shield Tunnelling ◽  
Slurry Shield

This paper presents the ground deformation induced by the large slurry shield tunnelling with a diameter of about 12 m in urban areas, which may challenge the safety of the existing nearby constructions and infrastructures. In this study, the ground deformation is analyzed by a three-dimensional finite difference model, involving the simulation of tunnelling advance, grouting, and grouting hardening. The transverse settlement, longitudinal settlement, and horizontal displacement of the ground are analyzed by comparing the simulation results with the field measurements in the Rapid Transit Line Project from Beijing Railway station to West Beijing Railway station in China. The numerical model proposed in this paper could well predict the ground deformation induced by large slurry shield tunnelling. The results show that the main transverse settlement occurs within the zone about 1.5 times of the excavation diameter, and the settlement during the passage of the shield and the tail void plays a most important role in the excavation process.

3D Analytical Solution of Soil Deformation Induced by Shield Tunnelling Construction

2011 ◽  
Vol 261-263 ◽  
pp. 1814-1819
Author(s):  
Gang Wei ◽  
Jie Hong ◽  
Xin Jiang Wei
Keyword(s):  
Analytical Solution ◽  
Ground Deformation ◽  
Three Dimensional ◽  
Analytical Calculation ◽  
Horizontal Displacement ◽  
Ground Movement ◽  
Soil Deformation ◽  
Loss Ratio ◽  
Shield Tunnelling ◽  
Ground Loss

Three-dimensional (3D) analytical solution of soil deformation induced by ground loss in shield tunnelling construction was researched. It is put forward that the ground loss ratio is not a fixed value, but changes in driving direction. The calculation formula of ground loss ratio in driving direction was deduced. Based on two-dimensional (2D) analytical solution of uniform ground movement model of shield tunnelling, the three-dimensional analytical solution of ground deformation induced by ground loss is deduced. The settlement in vertical direction and the displacement in lateral horizontal direction at any point can be calculated; and the method is only applied to the construction phase. In analytical calculation: the predicted soil displacements are in good agreement with the measured values, and the method is easy to use; the closer the soil to tunnel is, the faster the lateral horizontal displacement changes; the extent of change of lateral horizontal displacement in longitudinal direction is smaller than displacement in lateral direction.

Tunnel performance during the Puebla-Mexico 19 September 2017 earthquake

2020 ◽  
Vol 36 (2_suppl) ◽  
pp. 288-313
Author(s):  
Juan M Mayoral ◽  
Gilberto Mosqueda ◽  
Daniel De La Rosa ◽  
Mauricio Alcaraz
Keyword(s):  
Mexico City ◽  
Seismic Performance ◽  
Urban Areas ◽  
Numerical Study ◽  
Three Dimensional ◽  
Frequency Content ◽  
Seismic Performance Evaluation ◽  
Ground Deformations ◽  
Under Construction ◽  
Observed Damage

Seismic performance of tunnels during earthquakes in densely populated areas requires assessing complex interactions with existing infrastructure such as bridges, urban overpasses, and metro stations, including low- to medium-rise buildings. This article presents the numerical study of an instrumented tunnel, currently under construction on stiff soils, located in the western part of Mexico City, during the Puebla-Mexico 19 September 2017 earthquake. Three-dimensional finite difference models were developed using the software FLAC3D. Initially, the static response of the tunnel was evaluated accounting for the excavation technique. Then, the seismic performance evaluation of the tunnel was carried out, computing ground deformations and factors of safety, considering soil nonlinearities. Good agreement was observed between predicted and observed damage during post-event site observations. Once the soundness of the numerical model was established, a numerical study was undertaken to investigate the effect of frequency content in tunnel-induced ground motion incoherence for tunnels built in cemented stiff soils. A series of strong ground motions recorded during normal and subduction events were used in the simulations, considering a return period of 250 years, as recommended in the Mexico City building code. From the results, it was concluded that the tunnel presence leads to important frequency content modification in the tunnel surroundings which can affect low- to mid-rise stiff structures located nearby. This important finding must be taken into account when assessing the seismic risk in highly populated urban areas, such as Mexico City.

Study on the Method of Construction of Large Section Tunnel Crossing the Ancient Great Wall

2012 ◽  
Vol 226-228 ◽  
pp. 1504-1508
Author(s):  
Ai Bing Jin ◽  
Long Fu Li ◽  
Fu Gen Deng ◽  
Min Zhe Zhang
Keyword(s):  
High Efficiency ◽  
Surface Deformation ◽  
Ground Deformation ◽  
Three Dimensional ◽  
Horizontal Displacement ◽  
Tunnel Excavation ◽  
Construction Scheme ◽  
Construction Experience ◽  
Strata Deformation ◽  
Great Wall

While the tunnel crossing the ancient Great Wall, we must take effective measures to control ground deformation, prevent ground deformation is too large, destroying the heritage. In order to study the effects of tunnel excavation types on strata deformation, a three-dimensional computational model is built to simulate surface settlement and horizontal displacement by three different excavation types which are both-side heading method, CRD method, and hole pile method. Following comparative analysis, in line with the realistic program is recommended. The results show that both-side heading method can better control the surface deformation, and has a high efficiency of construction, which was selected as the construction scheme of tunnel crossing the ancient great wall. The results of this study are expected to provide construction experience to the works of a similar background.

scholarly journals Deformation information system for facilitating studies of mining-ground deformations, development, and applications

2014 ◽  
Vol 14 (7) ◽  
pp. 1677-1689 ◽  
Author(s):  
J. Blachowski ◽  
W. Milczarek ◽  
P. Stefaniak
Keyword(s):  
Data Mining ◽  
Information System ◽  
Spatial Data ◽  
Ground Deformation ◽  
Data Extraction ◽  
Three Dimensional ◽  
Horizontal Displacement ◽  
Spatial Data Mining ◽  
Calculation Of Parameters ◽  
Ground Deformations

Abstract. The paper presents the concept of the deformation information system (DIS) to support and facilitate studies of mining-ground deformations. The proposed modular structure of the system includes data collection and data visualisation components, as well as spatial data mining, modelling and classification modules. In addition, the system integrates interactive three-dimensional models of the mines and local geology. The system is used to calculate various parameters characterising ground deformation in space and time, i.e. vertical and horizontal displacement fields, deformation parameters (tilt, curvature, and horizontal strain) and input spatial variables for spatial data classifications. The core of the system in the form of an integrated spatial and attributive database has been described. The development stages and the functionality of the particular components have been presented and example analyses utilising the spatial data mining and modelling functions have been shown. These include, among other things, continuous vertical and horizontal displacement field interpolations, calculation of parameters characterising mining-ground deformations, mining-ground category classifications, data extraction procedures and data preparation preprocessing procedures for analyses in external applications. The DIS has been developed for the Walbrzych coal mines area in SW Poland where long-time mining activity ended at the end of the 20th century and surface monitoring is necessary to study the present-day condition of the former mining grounds.

Simulation of the Winter Meso-Scale Wind and Tidal Circulation in the Gulf of Patras (Greece)

2008 ◽  
Author(s):  
Nikolaos Th. Fourniotis ◽  
Georgios M. Horsch
Keyword(s):  
Wind Speed ◽  
Numerical Study ◽  
Three Dimensional ◽  
Field Measurements ◽  
Tidal Currents ◽  
Three Dimensional Model ◽  
Tidal Circulation ◽  
Gulf Of Corinth ◽  
Model Predictions ◽  
System 1

The Gulf of Patras is a shallow embayment (of 80 m mean depth), in western Greece, leading to the Ionian Sea on the west, and, through the straits of Rio-Antirio, to the Gulf of Corinth, on the east. In the present study, the three-dimensional modelling system [1] was applied to investigate the tide- and wind-driven circulation in the complex bathymetry of the natural basin of the Gulf of Patras. Numerical simulations have been conducted for different scenarios for wind speed and direction, and the results of the circulation forced by a uniform wind stress corresponding to a wind speed of 4 m/s and two different directions are reported. In addition, tidal records measured at both ends of the Gulf were used as forcing in order to simulate the tidal circulation. The numerical study corroborated that the tidal currents at the Rio-Antirio straits are stronger than those induced by the mean wind and are among the strongest tidal currents to be found in Greek waters. Comparisons between the three-dimensional model predictions and available field measurements have shown reasonable agreement both qualitatively and quantitatively.

scholarly journals Deformation information system for facilitating studies of mining ground deformations – development and applications

2013 ◽  
Vol 1 (5) ◽  
pp. 4801-4831
Author(s):  
J. B. Blachowski ◽  
W. Milczarek ◽  
P. Stefaniak
Keyword(s):  
Data Mining ◽  
Information System ◽  
Spatial Data ◽  
Ground Deformation ◽  
Data Extraction ◽  
Three Dimensional ◽  
Horizontal Displacement ◽  
Spatial Data Mining ◽  
Displacement Fields ◽  
Ground Deformations

Abstract. The paper presents the concept of the Deformation Information System (DIS) to support and facilitate studies of mining ground deformations. The proposed modular structure of the system includes data collection and data visualisation components, as well as spatial data mining, modelling and classification modules. In addition, the system integrates interactive three-dimensional models of the mines and local geology. The system is used to calculate various parameters characterising ground deformation in space and time, i.e. vertical and horizontal displacement fields, deformation parameters (tilt, curvature and horizontal strain) and input spatial variables for spatial data classifications. The core of the system in the form of an integrated spatial and attributive database has been described. The development stages and the functionality of the particular components have been presented and example analyses utilising the spatial data mining and modelling functions have been shown. These include, among other things, continuous vertical and horizontal displacement fields interpolations, calculation of parameters characterising mining ground deformations, mining ground category classifications, data extraction procedures and data preparation, pre-processing procedures for analyses in external applications. The DIS has been developed for the Walbrzych Coal Mines area in SW Poland where long-time mining activity has finished at the end of the 20th Century and surface monitoring is necessary to study present day condition of the former mining grounds.

Ground Deformation Rule Induced by Shield Tunneling Construction

2011 ◽  
Vol 90-93 ◽  
pp. 670-675
Author(s):  
Xin Jiang Wei ◽  
Yang Zhou ◽  
Gang Wei ◽  
Jie Hong
Keyword(s):  
Ground Deformation ◽  
Three Dimensional ◽  
Analytical Calculation ◽  
Horizontal Displacement ◽  
Tunnel Construction ◽  
Shield Tunneling ◽  
Dimensional Solution ◽  
Ground Loss ◽  
Good Agreement ◽  
Ground Displacements

In this paper, Ground deformation in shield tunneling construction is researched. It is put forward that ground deformation is caused by three reasons, which are ground loss, the positive thrust and the friction. By solving the three-part respectively, the three-dimensional solution formula can be obtained after superposing these. This method is used to calculate the tunnel construction phase at any point in the level of vertical settlement and horizontal displacement. As shown in analytical calculation, the predicted ground displacements of this method are in good agreement with the measured values.

scholarly journals Effect of Wet Deposition on Secondary Inorganic Aerosols Using an Urban-Scale Air Quality Model

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 168
Author(s):  
Kwandong D. Kim ◽  
Seungyeon Lee ◽  
Jae-Jin Kim ◽  
Sang-Hyun Lee ◽  
DaeGyun Lee ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Urban Areas ◽  
Wet Deposition ◽  
Three Dimensional ◽  
Field Measurements ◽  
Air Quality Model ◽  
Quality Model ◽  
Inorganic Aerosols ◽  
Washout Ratio ◽  
Microscale Model

We investigated the effects of wet deposition on secondary inorganic aerosols (SIAs) in urban areas by coupling the wet deposition module with the three-dimensional computational fluid dynamics atmospheric chemistry model (CFD-Chem). We developed a wet deposition model for the microscale model by improving on the global modeling initiative scheme. We evaluated the model by comparing it to the observed washout ratio from the total wet deposition. The simulated washout ratio calculated using the wet scavenging coefficient (WSC) based on the theoretical calculation is six times lower than that observed, suggesting that the wet deposition amount of SIAs from below-cloud scavenging might be underestimated. When we applied the WSC based on field measurements, the washout ratio was much improved; however, it was slightly overestimated compared to the observed rate. Therefore, we estimated the optimal WSC for SIAs in the urban area using a linear regression approach. We conducted a model using the wet deposition of SIAs in a megacity to understand the effects of wet deposition on the SIA concentration using estimated optimal WSCs. The simulated results indicate that washout processes decrease the surface aerosol concentration, showing that reductions in the average surface concentrations from washout processes were from 7.1% to 11.2%. The simulation results suggest that washout processes can reduce the particulate matter concentration in urban areas, indicating that washout processes should be considered in the microscale model, although the modeling domain can only simulate washout processes.

scholarly journals VISUALIZATION OF BIG GEODATA: AN EXPERIMENT WITH DINSAR DEFORMATION TIME SERIES

2019 ◽  
Vol XLII-4/W14 ◽  
pp. 135-141 ◽  
Author(s):  
C. E. Kilsedar ◽  
L. Frigerio ◽  
M. Bonano ◽  
G. Bordogna ◽  
P. Carrara ◽  
...  
Keyword(s):  
Time Series ◽  
Urban Areas ◽  
Ground Deformation ◽  
Three Dimensional ◽  
Data Generation ◽  
Synthetic Aperture Radar Interferometry ◽  
Use Of Time ◽  
Deformation Velocity ◽  
Data Assessment ◽  
Spatio Temporal

<p><strong>Abstract.</strong> This paper describes an experiment carried out within the project “URBAN GEOmatics for Bulk data Generation, Data Assessment and Technology Awareness (URBAN GEO BIG DATA)” on novel technological solutions for encouraging the use of time series of big geodata by scientists, public administrators, and the citizens of urban areas. In this experiment, we focus on fostering the use of ground deformation time series derived through the Differential Synthetic Aperture Radar Interferometry (DInSAR) measurements in urban areas (i.e., Naples, Milan, and Turin) through visualization. Two visualization applications are developed within the project. First, mean deformation velocity maps are visualized; second, the cumulative deformation time series is animated to enable the comprehension of deformation of eighteen years at a glance. The experiment allows experts and non-experts to discover spatio-temporal patterns of deformation. The paper focuses on the characteristics and implementation details of this experiment. Both visualizations are overlaid on a three-dimensional map, i.e., a virtual globe. We use open standards and free and open source software (FOSS) for Web to enable interoperability, replicability, and reusability.</p>

EXPERIMENTAL AND NUMERICAL STUDY OF THREE-DIMENSIONAL NATURAL CONVECTION AND FREEZING IN WATER

1994 ◽  
Author(s):  
C. Abegg ◽  
Graham de Vahl Davis ◽  
W.J. Hiller ◽  
St. Koch ◽  
Tomasz A. Kowalewski ◽  
...  
Keyword(s):  
Natural Convection ◽  
Numerical Study ◽  
Three Dimensional
Sign in / Sign up

Export Citation Format

Share Document